1. Field of the Invention
The present invention relates to a structure for fixing permanent magnets in a motor used in vehicle electrical equipment or the like.
2. Description of the Related Art
In a motor used, for example, in vehicle electrical equipment, a thermosetting adhesive is generally used for fixing permanent magnets to an internal peripheral surface of a motor yoke made of a ferromagnetic substance. However, in this case, a long period of time is required for hardening of the adhesive and the permanent magnets sometimes slip in the course of hardening of the adhesive. The motor using such an adhesive also has a problem with respect to the danger that the permanent magnet is broken due to the thermal stress acting thereon during generation of heat in the motor.
A method of fixing permanent magnets to the internal peripheral surface of a yoke using a separate mounting member is thus proposed. However, this method has not only the problem that it is troublesome and complicated to position the permanent magnets but also the problem that it is difficult to precisely mount the permanent magnets without producing looseness. Thus, this method cannot be immediately employed.